The present invention is directed generally to a vascular prosthesis which is useful in repair or replacement of a branched section of a blood vessel. More particularly, the present invention provides a textile vascular graft which is particularly useful in branched end-to-side anastomoses of the aorta and its arterial branches.
The use of tubular textile fabrics for soft-tissue implantable prostheses is well known in the repair or replacement of damaged or diseased lumens in the body. For example, tubular devices or conduits are used to repair lumens such as in the esophagus and colon areas, and, in particular, prostheses are used in the vascular system to repair, buttress or replace a weakened section of the vessel. Such conduits are generally affixed in a specified location in the vessel by means of sutures, stents, hooks or other mechanisms which serve to secure the device in place.
Synthetic vascular grafts for the repair or replacement of blood vessels have taken a wide variety of configurations and shapes. The most common type of vascular graft is that manufactured in a generally tubular form extending along a relatively straight longitudinal axis. Such tubular vascular grafts are particularly well suited for use in end-to-end anastomoses, i.e., where the damaged portion of the blood vessel is dissected and the ends of the tubular graft are connected to the cut ends of the blood vessel to span the dissected portion. These tubular grafts may also be used in end-to-side anastomoses, i.e., where the end of a blood vessel is attached to the side of a graft tube or where the end of a graft tube is attached to the side of a blood vessel. Such tubular vascular graft configurations are also useful in endovascular applications, where the graft is inserted percutaneously and is positioned to span a damaged or diseased portion of a blood vessel without conventional surgery.
For branched end-to-side anastomoses of the aorta and its arterial branches it is necessary to provide an end-to-side vascular graft in which the side branch portion extends substantially perpendicular from the main portion to replace a portion of a blood vessel or to be positioned within a portion of a vessel which splits into one or more branch vessels. One such conventional graft is an aortic arch graft 10 shown in FIG. 1. Graft 10 includes an elongate main tube 12 and a plurality of aligned branch tubes 14 extending from the main tube 12 in generally parallel fashion. In certain situations where the aortic arch graft is designed to be temporarily connected to external devices, such as for example, a heart-lung machine, the graft 10 may include a lateral branch 16 extending from main tube 12 at a location spaced from the aligned branches 14.
Such end-to-side vascular grafts have typically been constructed by suturing one tubular vascular graft to the side of a second tubular vascular graft. Such end-to-side vascular grafts are used, for example, to repair or replace a damaged or diseased portion of the aorta. In such procedures, an aortic vascular prosthesis which includes a main aortic trunk portion and arterial branch portions extending generally perpendicular to the main aortic trunk portion for the left and right carotid arteries and the subclavian artery is particularly well suited. In order to provide an aortic vascular prosthesis with three branches, a surgeon will typically suture three separate straight tubular vascular grafts to the side of a larger tubular graft. Such suturing, however, usually occurs immediately prior to or during a procedure, is labor intensive and requires extreme skill and precision in suturing, thereby introducing the potential for human error.
Prior art end-to-side vascular grafts, such as the aforementioned aortic vascular prostheses, have not been completely successful. In particular, it has been sometimes difficult to correctly position the graft at the aortic arch region because the prior art grafts have been substantially straight or just slightly arched while the aortic arch is substantially curved. Furthermore, prior art grafts typically kinked when deformed or bent to a curve which anatomically contours the curvature of the aortic arch. Such kinking further complicates the placement of the graft during surgery.
Accordingly, there is a need for a vascular graft which has a configuration more favorable for implantation at the aortic arch region and which can better conform to the natural curvature of the aortic arch in a human. Furthermore, there is a need for a vascular graft which does not kink and which maintains a fully open lumen when shaped to the natural curve of the aortic arch.
The present invention is an implantable textile prosthesis which is anatomically curved to substantially match the natural curvature of the aortic arch in a human being or patient. The prosthesis has a first woven section having an elongate tubular main wall having a first and a second open end defining a fluid passageway therethrough. The first woven section is arched to define an apical region and to conform generally to an aortic arch of a human patient. A plurality of elongate woven tubular extents extend vertically from a top wall portion at the apical region of the tubular main wall. These tubular extents are sutured to the first woven section to provide fluid communication between the tubular main wall and the tubular extents.
In one aspect of the present invention, the prosthesis has a radius of curvature of the main elongate wall of from about 20 mm to about 80 mm creating an arc of about 15 to 90 degrees. Moreover, the lateral wall portions of the first open end, the apical region and the second open end of the prosthesis may be substantially planar or may be skewed from about 2 degrees to about 30 degrees.
In another aspect of the present invention, an arched implantable textile prosthesis is provided. The prosthesis includes a first woven section having an elongate tubular main wall with a first and a second open end defining a fluid passageway therethrough. The first woven section is arched to define an apical region of the main tubular wall with a radius of curvature from about 150 mm to about 300 mm. The first woven section can be further manipulated during implantation to a radius of curvature of from about 20 mm to about 80 mm to conform generally to an aortic arch of a patient without kinking of the tubular main wall. The prosthesis also includes a plurality of elongate woven tubular extents extending vertically from the top wall portion at the apical portion of the tubular main wall. These tubular extents are sutured to the first woven section to provide fluid communication between the tubular main wall and the tubular extents.
In yet another aspect of the present invention, a method for producing anatomically curved or significantly arched tubular prostheses is provided. The method includes weaving a first woven section having an elongate tubular main wall having a first and a second open end defining a fluid passageway therethrough; providing a curved mandrel having a radius of curvature generally conforming to the curve of an aortic arch of a human patient; placing the first woven section over the mandrel; heat setting the first woven section to set the shape of the first woven section; and removing the first woven section from the mandrel to provide an anatomically curved tubular main wall. Alternatively, the arched tubular prosthesis is woven into the anatomically curved shape.
In yet another aspect of the present invention, there is provided a method of treating a patient in need of an aortic arch prosthesis comprising an anatomically curved or significantly arched tubular prosthesis having a main tubular portions having opposed open ends and lateral tubular branches; preparing portions of an aorta of the patent for surgery and reception of the prosthesis; connecting one end of the main tubular portion to the descending aorta; connecting the aortic arteries to the lateral tubular branches; and connecting the other end of the main tubular portion to the ascending aorta to provide fluid communication among the ascending aorta, the aortic branches and the descending aorta.